Apple has announced iPhone 4.0, available for developers in beta form starting today and arriving for iPhone and iPod touch users sometime this summer, and iPad users in the fall. Highlights of the latest version of the mobile OS that powers the iPhone, iPod touch, and iPad include the following 7 "tentpoles":

  1. Multitasking (iPhone 3GS/iPod touch G3 only)
  2. Folders with intelligent naming
  3. Mail with unified inbox, multiple Exchange accounts, threaded messages
  4. iBooks for iPhone
  5. Increased Enterprise support in iPhone 4.0
  6. Game Center social network
  7. iAd mobile advertising platform

iPhone 4.0 will also bring iPhone 3.2 (iPad) features like spell checking, Bluetooth keyboard support, Home Screen wallpaper, a 5x digital zoom (and tap to focus for video), as well as 1500 new API for developers (like -- finally! -- calendar access!)

How's that list looking to you?